Viral pathogenic mechanism Flashcards
What are the sites of viral entry
conjuntivia capillary skin digestive tract respiratory tract
Latent infection
Virus that lies dormant then is triggered and returns
Example of latent infection
Herpes simplex virus:
cold sores
genital lesions
example of an acute virus infection
Influenza a virus - respiratory infection
neurological infections -
Enteric infections - occur in intestine
What can viral infections become
bacterial
What is viaremia
Virus going into the blood
Where are acute viral infections localised
to specific part of the body
What happens in influenza viral infection
Destruction of respiratory epithelium
Altered cytokine expression leading to fever
Where is enterovirus excreted
faeces
Development of Viraremia is bad because
causes widespread infection of tissues and if enters neuronal tissue causes paralysis
What is antigenic drift
Gradual evolution of viruses to generate antigenic variants
Generation of novel influenza viruses due to
antigenic drift
antigenic shift
what is antigenic shift
Significant changes in virus antigenic structure
What plays a main role in antigenic shift for influenza virus
confection with nonhuman hosts
eg avain virus - bird flu
swine influenza
What is a enterovirus
any of a group of RNA viruses which typically occur in the gastrointestinal tract, sometimes spreading to the central nervous system or other parts of the body.
What is examples of enterovirus
Poliomyelitis (poliovirus) - paralysis
Meningitis - meniges to much
Myocarditis (inflammation of the heart muscle) Pancreatitis - inflammation of the pancrease
What diseases does coxsackie B viruses cause
Pancreatitis
Myocarditis
What does poliovirus result in if become neurological
muscle weakness, leading to paralysis
In Herpes viral latent infection where does the virus migrate to and remains
migrates to ganglia
and remains latent in the nucleus
give two examples of viral induced tumours
Papillomaviruses – cervical cancer
Retroviruses – lymphomas (cancer of the lymph nodes)
-leukaemias (decreased WBC)
What does a retro virus do
modifies host cells gene expression using trans-activating protein resulting in tumour formation
